@hocuspocustocus I've moved your post to the Sims 4 PC tech section.
Please remove your entire Sims 4 game folder from Documents\Electronic Arts—you can just put it on your desktop. When you launch the game, a clean folder will spawn with no content. Does it work now? If so, the issue is something in your old game folder. To find out, move your content from the old folder to the new one in batches, testing the game each time to make sure it still works. Any batch that causes another white screen needs to be split and tested again until you've found the problem file(s).
Here's a list of everything you'll find in your game folder. Some of the files don't need to be put pack, as the game will recreate them as necessary.
https://sims4.crinrict.com/eng/2014/09/user-files-explained/
If you still see a white screen even in a clean game folder, please run a dxdiag and attach the results to a post here.
https://help.ea.com/en-us/help/pc/how-to-gather-dxdiag-information/